Meter connection device



Dec. 5, 1939.

E. G. JoHANssoN 2,182,629

METER CONNECTION DEVICE Filed March 9,' 1938 UNITED STATES PATENT OFFICE METER CONNECTION DEVICE Ernest G. Johansson, Watertown, Mass., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania.

Application March 9, 1938, Serial No. 194,839

5 Claims.

The present invention relates to a mounting for watthour meters or other electrical instrumentalities and is concerned particularly with the mounting of such instru type of casing used for mentalities housed in the watthour meters of the so-called detachable type.

This type of construction is shown, for example, in Patent 1,969,4 to Bradshaw et al. In

the meter casing has contact blades 99, issued August 7, 1934, this type of construction projecting from the base thereof or detachable association with complementary contact jaws disposed on a support for connection to the circuit to be metered. With specific reference to watthour meters, although the thereto, it is frequently invention is not limited desired to mount a plurality of meters on a channel or trough to make a compact assembly for building,

the various circuits of a or it may be desirable to mount one of such meters on a receptacle or housing substantially larger than bered patent, so that that shown in the above numother electrical apparatus or more elaborate circuit connecting devices may be sealed within such receptacle or housing.

In the copending application of Bradshaw and Johansson Serial No. 118,590, iiled December 31,

1936, one type of constr uction for so mounting a meter is disclosed. In this application the receptacle is provided with a terminal block secured therein to the back thereof and has contact jaws supported across the open front of the box. Conducting straps extend from the terminal block and the jaw with the free ends thereof adjacent to, but out of contact with, each other. By means of a screw extending loosely through a hole in the end of one strap into threaded engagement with the free end of the other strap, the free ends may be clamped together when the screw is tightened, and when the screw is loosened the free ends will tion hole in said one resiliently separate and the electrical connecwill be broken by reason of the fact that the strap is larger than the shank of the screw. This construction has been used quite extensively, but not the final answer kind because when it is loosened, the

it is recognized that it is for an installation of this of the possibility of losing the screw difficulty of inserting the screw because due to manufacturing discrepancies the holes in the fre e ends of the straps may not be in exact alinement, and it is somewhat unsatisfactory to depend upon the resiliency of the straps for the separation of the free ends.

In the copending application of Johnson Serial No, 100,840, filed September 15, 1936, a modified construction is shown wherein the mechanical (Cl. 20G- 158) and electrical disconnection of the free ends of the straps is accomplished. The construction shown insures that the member which connects the free ends is positively moved out of its operating position. This construction has met with Il' the construction shown in the copending applica- 15'2 tion of Bradshaw and Johansson.

i Other objects of the invention will be apparent from the following description and accompanying drawing in which the single figure is a view of a meter mounting in accordance with the invention, portions of the receptacle being shown in section.

Referring to the drawing, a receptacle 2 which may be part of an elongated trough, or box for accommodating a single meter, is preferably formed of sheet metal with bottom and side walls and is closed by a cover The cover 4 is provided with a circular aperture which is surrounded by an upstanding ring which is secured to the cover in any suitable manner as by upsetting projections 8 depending from the ring through holes provided in the cover. The ring is proportioned to seat a watthour meter of the detachable type with the base of the meter closing the aperture when it is suitably clamped to the ring.

The ring is provided, preferably integrally therewith, with a diametrically extending bar or support l to which is secured, as by screws l2, a pair of porcelain blocks I4. This construction is more clearly .shown in the copending application of Johnson Serial No. 171,385. Contact jaws I6 are secured to the porcelain blocks as by screws i8 extending upwardly through the block and base of the jaw into threaded engagement with conducting straps 20, the free ends of which are bent at right angles to extend toward the base or rear wall of the receptacle.

Terminal blocks 22 of suitable insulating material are secured to the base or rear wall of the receptacle 2 in any desired manner and each is provided with a terminal clamp 24 for receiving the conductors or buses of a circuit to be metered. Clamps of the type intended are quite well known and are shown specifically in U. S. Patent 2,088,481 issued July 27, 1937.

A conducting strap 26 is secured at one end to each of the terminal clamps 24 and extends laterally and then at right angles, terminating in a free end 28 confronting the depending portion of a jaw strap 26. Each strap 26 is provided with an angularly disposed portion 30 which is apertured to loosely receive a clamping screw 32, the lower end of which is reduced to extend through an aperture in the lower end of the strap and upset to prevent its removal without, however, interfering with its rotation. y

A claimping member or bracket 34 is threaded on each of the screws 32 for movement toward or away from the jaw straps 26, depending upon the direction in which the screw is turned. The member 34 is provided with an angularly bent portion 36 which at one limit of travel will be disposed behind the depending part of the jaw strap, that is, on the side of such strap remote from the free end 28 of the strapv 26. At the other limit of travel the portion of the member 34 on the side thereof remote from the strap 26 will engage an adjustable screw or stop 36. Accordingly the member 36 will be positively moved toward or away from the strap Z6 upon rotation of the screw 32 and the member is prevented from rotating during such movement by reason of its squared end sliding along the iat face of the strap 26.

In assembling the structure the terminal strap 26 with its free end 2B may be in the position shown at the left in the drawing. It will be noted here that the screw 32 has been backed 01T so far that the member 34 has been forced against the stop 38 with suflicient force to cause the screw and the strap 26 to tilt to the left. This ensures that the free end 28 is out of the path of the jaw strap 20.

When the cover with its jaws i6 and straps 2U is secured in place, a screwdriver may be manipulated through the opening in the cover to turn down the screw 32. This will raise the r member 34 out of engagement with the stop 38 and permit the strap 26 to move resiliently toward the strap 20. This may or may not be suiicient to bring the free end 28 into contact with strap 20.

Upon continued turning of the screw, the member 34 will arrive at a position where its angular portion 36 will be disposed behind the strap Z6 when the member approaches its upper limit of travel adjacent to the sloping surface 3D of the strap. Further turning of the screw in the same direction will, because of the flexibility of the strap 26, force the strap portion 30 toward the member 34 to jam the strap end 28 against the strap 2U and, at the same time, draw the angular portion 36 of member 34 against the opposite side of strap 20 to` resiliently and forcibly clamp the elements together, as shown to the right in the drawing.

By reason of the construction shown, an unusually rugged and e'icient disconnecting device has been provided. When it is desired to disconnect a consumers service, it is merely necessary to remove the meter and by manipulation of the screw 32, move the member 34 to its lowermost position where the strap 26 will be positively moved laterally of the strap 2Q and out of contact therewith. When the meter is replaced and sealed in position, access to the screw 32 is, of course, prevented.

Quite apparently modications in the specific construction shown are possible, and it is intended that the invention shall be limited only by the scope of the appended claims.

I claim as my invention:

l. In an installation for mounting an electrical instrument of the type having contacts projecting from the base thereof, a receptacle having a terminal block therein with terminal clamps mounted thereon, conducting straps extending from each clamp toward an open side of the receptacle, contact members mounted across said open side for cooperation with said instrument contacts and conductors depending therefrom adjacent to said straps, means for releasably connecting a strap to an adjacent conductor including a screw and means for rotatably mounting it, a clamping member threaded on said screw and movable upon rotation of the screw along said strap between two limits of travel, and

means operable at the limit of travel remote from said conductor for forcing said strap away from said conductor.

2. In an installation for mounting an electrical instrument of the type having contacts projecting from the base thereof, a receptacle having a terminal block therein with terminal clamps mounted thereon, conducting straps extending fro meach clamp toward an open side of the receptacle, contact members mounted across said open side for cooperation with said instrument contacts and conductors depending therefrom adjacent to said straps, means for releasably connecting a strap to an adjacent conductor including a screw and means for rotatably mounting it,

a clamping member threaded on said screw and movable upon rotation of the screw along said strap between two limits of travel, and means operable at the limit of travel remote from said conductor for causing said member, screw and strap to tilt laterally away from said conductor.

3. In an installation for mounting an electrical instrument of the type having contacts projecting from the base thereof, a receptacle having a terminal block therein with terminal clamps mounted thereon, conducting straps extending from each clamp toward an open side of the receptacle, contact members mounted across said open side for cooperation with said instrument contacts and conductors depending therefrom adjacent to said straps, means for releasably connecting a strap to an adjacent conductor including a screw and means for rotatably mounting it, a clamping member threaded on said screw and movable upon rotation of the screw along said strap between two limits of travel, the limit of travel remote from said conductor being defined by a projection secured to said terminal block in the path of movement of a portion of said member at the side of said screw remote from said strap to cause the member to tilt into engagement with the strap to force the latter away from said conductor when the member is screwed down against said projection.

4l. In an installation for mounting an electrical instrument of the type having contacts projecting from the base thereof, a receptacle having a terminal block therein with terminal clamps mounted thereon, conducting straps extending from each clamp toward an open Side of the receptacle, contact members mounted across said open side for cooperation with Said instrument contacts and conductors depending therefrom adjacent to said straps, means for releasably con-v necting a strap to an adjacent conductor comprising a screw rotatably mounted on said strap with the head thereof accessible from said open side of the receptacle, a clamping member in threaded engagement with said screw and movable along the strap, upon rotation of the screw between two limits of travel, an angular portion on said member for disposition at the side of the conductor remote from the strap at one limit of travel and away from the conductor at its other limit of travel, the end of the member on the side of the screw remote from said angular portion being squared to slide along the strap whereby rotation of the member is prevented, and means eiective at said one limit of travel upon continued rotation of the screw for causing said member to tilt to clamp the conductor between the strap and said angular portion.

5. In an installation for mounting an electrical instrument of the type having contacts projecting from the base thereof, a receptacle having a terminal block therein with terminal clamps mounted thereon, conducting straps extending from each clamp toward an open side of the receptacle, contact members mounted across said open side for cooperation with said instrument contacts and conductors depending therefrom adjacent to said straps, means for releasably connecting a strap to an adjacent conductor comprising a screw rotatably mounted on said strap with the head thereof accessible from said open side of the receptacle, a clamping member in threaded engagement with said screw and movable along the strap upon rotation of the screw to two limits of travel, an angular portion on said member for disposition at the side of the conductor remote from the strap at one limit of travel and away from the conductor at its other limit of travel, the end of the member on the side of the screw remote from said angular portion being squared to slide along the strap whereby rotation oi the member is prevented, and means effective at said one limit of travel upon continued rotation of the screw for causing said member to tilt to clamp the conductor between the strap and said angular portion, said means including an angular surface on said strap engaging the squared end of said member.

ERNEST G. JOHANSSON. 

